Definition - What does FMF Threesome mean?

Kinkly explains FMF Threesome

There are basically two different types of threesomes: a threesome where there is bisexual play between the two individuals of the same sex, and a threesome where there is no bisexual play between the individuals of the same sex. An acronym in which the letters signifying the same sex are placed back to back (FFM, MMF) indicates a threesome in which there is bisexual activity. An acronym in which the two letters are separated by the letter signifying the opposite sex (FMF, MFM) indicates that there is no bisexual activity. An FMF threesome involves no female-female sexual action, while a FFM threesome does include female-female sexual activity.